1. Field of Invention
The present invention relates to a semiconductor composite film with a heterojunction and a manufacturing method thereof, especially a semiconductor composite film with a heterojunction capable of mitigating strain, and a manufacturing method of the semiconductor composite film.
2. Description of Related Art
FIGS. 1A-1C show cross section views of a semiconductor composite film 100 formed by a semiconductor substrate 11 and a heterogeneous semiconductor epitaxial layer 13, and a heterojunction is formed in between. As shown in FIG. 1A, before forming the semiconductor epitaxial layer, the surface of the semiconductor substrate 11 is substantially flat. After forming the semiconductor epitaxial layer on the semiconductor substrate 11, the heterojunction between heterogeneous materials causes tensile or compressive stress and a tensile or compressive strain is accordingly generated to cause bending, as shown in FIGS. 1B and 1C.
In general, after manufacturing the semiconductor composite film with a heterojunction, some subsequent manufacturing processes will be performed such as heat treatment or surface mechanical polishing, which can easily cause cracking. Therefore, either the yield is unsatisfactory, or a protection process or measure should be taken, both of which will increase the manufacturing cost.
In view of the above, the present invention provides a semiconductor composite film with a heterojunction and a manufacturing method thereof, which are capable of mitigating the strain to provide a more robust semiconductor composite film, and to reduce the manufacturing cost.